1. Field of the Invention
The present invention relates to a reproducing apparatus of an optical information recording medium for reproducing recorded information from the optical information recording medium in which the information is recorded on a disc-like medium with pits or the like, or a recording/reproducing apparatus being further possible to record information (hereinafter, it is called only by a recording/reproducing apparatus of an optical information medium), and in particular to an information recording/reproducing apparatus being able to record the information of a plurality of sectors as one recording unit onto the optical information recording medium, in which recording area is formed with a plurality of zones and a sector number for one round on a track is different for each of the zones.
2. Description of Related Art
Conventionally, various kinds or types of recording/reproducing apparatuses for optical information recording medium are already known and are in practical use, which read out the recorded information optically for reproduction thereof, from an optical information recording medium on which the information is recorded by forming pits with use of so-called a phase-change or the like on a disc-like optical recording medium. In particular, recent years, an optical recording medium, being able to record a large amount of information with high density in the recorded information, was proposed and is now attracting attentions, for example that called by a "DVD" (digital versatile disc), and also a reproducing apparatus for reading out the information therefrom, but only a part of products thereof, is already available on a market.
However, with such the high density recording medium including such as the DVD, etc., for the purpose of increasing the density in information recorded on the disc-like medium, a laser beam is applied to, being shorter in the wavelength than that used in previous, and further for the purpose of increasing the density in track pitch, a concave portion and a convex portion, being called "a groove area" and "a land area" respectively, are formed on the recording surface of the medium, so as to record the information in those areas. More, the land area or the groove area appears alternatively for each round, following a tacking operation by an optical pickup as an optically reproducing means. Also, as such the high density recording mediums, there are proposed various kinds of recording mediums, such as a recording medium which enables only reproduction of the information recorded, a recording medium which enables recording of only one-time, and further a recording medium which enables a plurality of times of recordings, etc. However, among those kinds of the recording mediums, characteristics or properties are different to one another, in particular in reflectivity or reflection factor thereof.
On a while, in a recording/reproducing apparatus of optical recording medium for reproducing the recorded information from such the high density recording medium, in which such the concave and the convex portions, called as the land area and the groove area, are formed, conventionally, a control is applied for controlling a focus position of the optical reproducing means thereof, in which the focus position for the land area and the focus position for the groove area are exchanged alternatively, for each round, in synchronism with an address signal recorded in advance, in an area defined between the land area and the groove area, namely called by a pit address.
Also, from conventionally, a high reliability of the information is achieved by conducting a so-called verify control, i.e., it is verified or confirmed whether the recorded data can be reproduced correctly or not when recording information onto the optical recording medium.
However, for reproducing the information recorded with high density, it is necessary to control an optical pickup as the optical reproducing means, in particular the focus position of the focus lens, with higher accuracy. Ordinarily, with the recording/reproducing apparatus for optical information medium, the focus position is adjusted so as to be controlled at an appropriate position obtained in advance when being shipped, however, it is important to control the focus position at an appropriate position in conformity with, for example, the kind and/or condition of the recording medium, and further an environment of use of the apparatus, including the temperature and soon. For that purpose, modifying the focus position to an ideal position is conducted on a basis of the recorded data which is reproduced actually with the apparatus by applying a control, such as a learning control, etc.
However, as mentioned in the above, when controlling the optical pickup to the ideal or optimal position by paying attention only to the focus position for reproducing the information by means of the focus position control such as the learning control, etc., there should occur a problem in the reproduction of the address information recorded in the pit address area defined between the above-mentioned land area and groove area.
Namely, as is mentioned previously, the focus position of the optical pickup is controlled by exchanging between the focus position for the land area and the focus position for the groove area alternatively in synchronism with the address signal in the above pit address area. However, when the focus position of the above optical pickup is controlled to the position being optimal only for reproducing the recorded information in the land area or the groove area, it happens a case the address information in this pit address area cannot be read out correctly.
However, in the case where the address information in this pit address area cannot be read out correctly in this manner, since various operations, including the reproduction or the recording of the information, are performed on the basis of the address information in this pit address area with such the apparatus, it is impossible to ensure total operations of the recording/reproducing apparatus including a tracking control of the above optical pickup, and then the apparatus cannot accomplish the role as the recording/reproducing apparatus.
Further, the idea of the verify control itself was already known from conventionally, however, no teaching was given about the verify control on the optical information recording medium, in which the recording area is formed with a plurality of zones and the sector number is different for each of the zones.